we are still trying to get to the real story on tamerlan tsarnaev's trip to russia last year and his possible ties to terrorism and islamic extremism. chief intelligence correspondent catherine herridge is following that thread tonight. >> the fbi's handling of tamerlan tsarnaev in 2011 and six-month trip to russia the following year now face congressional scrutiny. >> was your department aware of his travels to russia and, if you weren't, the reason? >> yes. the system pinged when he was leaving the united states. by the time he returned all investigations had been -- the matter had been closed. >> napolitano said the lookout system that flags agents federal investigation no longer active when tamerlan returned from russia in july of 2012. >> the system picked up departure but did not pick him coming back, correct? >> the fbi text alert on him at that point was more than a year old and had expired. >> napolitano's pluck contradict briefing given by the fbi director. >> after talking to the fbi they told me they had no knowledge of him leaving or coming back. the name was misspelled.